Treadmill Exercise Prevents Recognition Memory Impairment in VD rat model through Enhancement of Hippocampal Structural Synaptic Plasticity

In vascular dementia (VD), memory impairment caused by the damage of synaptic plasticity is the most prominent feature that afflicts patients and their families. Treadmill exercise has proven beneficial for memory by enhancing synaptic plasticity in animal models including stroke, dementia, and mental disorders. The aim of this study was to examine the effects of treadmill exercise on recognition memory, and structural synaptic plasticity in VD rat model. Here, our study demonstrated that VD rat exhibited significantly recognition impairment, while treadmill exercise improved recognition memory in VD rat. To further investigate potential mechanisms for the treadmill exercise-induced improvement of recognition memory, we examined hippocampal structural synaptic plasticity by means of transmission electron microscopy and golgi staining in VD rat that had undergone 4 weeks of treadmill exercise. The results demonstrated that VD rat causes the damage of structural synaptic plasticity. However, treadmill exercise led to increases in synapse numbers and the number of dendritic spines in VD rat. Together, the improvement of VD-associated recognition memory by treadmill exercises is associated with enhanced structural synaptic plasticity in VD rat model.